I upgraded leap15.5 to 15.6 yesterday, There are a lot of issues that I’ve posted in the forum.
list of them:
input sound not working
New one is: Shutdown/Restart hang occasionally, not always. So I have to push power button manually!
6.4.0-150600.23.17-default
When you hit the Esc key, is nothing shown as an explanation?
nothing happened, it’s freezed
I’d try a different reboot option (kernel boot parameter):
reboot=efi
reboot=pci
There’s others too; I like efi because it makes my laptop hard-reboot (I like my reboots to be sure 
)
This might only help if it’s the actual state of reboot freezing, vs oS/kernel freezing before it does that step.
If that solves the issue, that implies there’s something up with that computer’s ACPI while rebooting (not too sure where to start with that though)